Incandescent lamp base



Dec. 17, 1968 p, DAYTON ETAL 3,417,367

INCANDESCENT LAMP BASE Filed June 28, 1967 5s 54 so 54 5e DAVID R. DAYTON ALBERT H. NIMBLETT JR.

INVENTORS ATTOR N E Y United States Patent 3,417,367 INCANDESCENT LAMP BASE David R. Dayton, Beverly, and Albert H. Nimblett, Jr., Salem, Mass., assignors to Sylvania Electric Products, Inc., a corporation of Delaware Filed June 28, 1967, Ser. No. 649,579 4 Claims. (Cl. 339-445) ABSTRACT OF THE DISCLOSURE A snap-on base and socket arrangement that can be used with tubular incandescent lamps which have press seal ends. The glass press seal of the lamp is provided with formed notches for locating and retaining a pair of electrical side runners thereon. Filament lead-in wires of the lamp are electrically connected to the inside of the runners prior to sliding a ceramic yoke over the runners thereby bridging them together. A pair of ears extending from the lower edges of the runners are bent over the base of the yoke securing it to the lamp seal.

This completed lamp base can then be snap-fitted into a ceramic socket the interior of which is provided with a pair of spring-metal electrical connectors. A bent detent protrusion on the spring connectors mates with the notches of the side edges of the lamp base, thereby retaining the lamp within the socket.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to tubular lamps having at least one flattened sealed end and to an improved lamp base and socket. More particularly, the units concerns a lamp base of the type that does not require cement for securing. This mechanical type base, when assembled, can be snapfitted to a mating socket capable of supporting the lamp in axial alignment.

Description of prior art In the general procedure of basing tubular lamps having press-sealed ends, a cement is required for attachment. Usually, a base is cemented onto a lamp seal after proper electrical connections are made by welding one lead-in wire to the shell of the base and the other wire to the bottom contact button. The use of cement to adhere the base shell to the lamp presents many problems. One major problem is that valuable time is taken in curing the base cement. The curing of the cement is usually done while the lamp and base shell are held in fixed axial alignment, usually in a bench jig or other suitable mechanism. Improper cementing techniques in this step of fabrication can produce a high rejection of the finished lamps. The alignment of the lamp during these steps of fabrication is also very critical, especially to the final operational quality of lamp. These problems mentioned above are only a few that make the basing lamps with cement an expensive and time-consuming operation.

SUMMARY OF THE INVENTION In our present invention, we have overcome the abovementioned problems by utilizing the normal shape of the press-seal as a foundation upon which we attach a mechanical base. The only modification made to the standard press-seal is the provision of a notch in each side edge of the seal. Thereafter a pair of metal runners having retaining means such as indented tabs corresponding to the above-mentioned notches are then assembled on the seal edges. These runners also serve as electrical connectors to the lamp filament by way of the lead-in wires of the lamp. One lead-in wire is connected to the inside "ice of each runner by an intermediate wire provided with a suitable fuse link. After these lead-in wires are electrically connected to the runners, a ceramic yoke is attached to the base, bridging the runners together. The bottom part or base of the ceramic yoke covers and protects the electrical fuse connections and a pair of tabs protruding from the bottom of the runners are bent over the base of the yoke, securing it to the press seal.

We also provide a lamp socket that mates with the above-described lamp base, the interior of which has a pair of electrical connector strips positioned to contact the runners of the base. These connector strips are spring biased inwardly and are provided with detent nodes positioned to coincide with the indented tabs of the base runners. With this particular type of arrangement, a based lamp can easily be snapped into and out of a socket.

BRIEF DESCRIPTION OF THE DRAWING FIGURE 1 is an exploded view showing the lamp, runners and yoke prior to assembly.

FIGURE 2 is a perspective view, partly in section, of the completed lamp.

FIGURE 3 is an enlarged view in section of the base of the lamp in a mating socket.

DESCRIPTION OF PREFERRED EMBODIMENTS In reference to the drawings, the mechanical base and socket we wish to disclose is shown in enlarged detail. The novel base and socket shown is for a single-ended lamp but may be adapted for utilization with doubleended lamps.

In FIGURE 1, a tubular incandescent lamp 10 is shown fabricated from a quartz glass having a high silica content. In the particular lamp shown, a suitable filament 12 is illustrated to show the typical support wires 14 and the appropriate lead-in wires 16 and 18 that are spliced at the seal to molybdenum ribbon foils 20. The seal 22 is flattened by a convetnional press-seal operation. As shown in the drawings, the press-seal operation compresses the glass around the molybdenum ribbons 20 and lead-in wires to completely seal the lamp from the outside atmosphere. The outer edges of the seal are left with slightly raised edges or ribs 23 on either side of the seal.

A pair of notches 24 are formed midway along the length of the ribs and to a depth of about one-half of their thickness. These notches 24 can be formed during the conventional press seal operation, if necessary, at a later stage of the assembly.

The lead-in wires 16 and 18 also extend from the ribbon seals 20 to the exterior of the lamp. Each lead-in wire is provided with a fuse wire 26 that electrically connects the lead-in wires 16 and 18 to a pair of metal runners 28. The shape of the runners 28 is formed to coincide with the shape of the raised ribs 23. This allows the runners 28 to be slid over the ribs 23. A track like portion 30 of the runners lies partially on the surface of the reduced portion 32 of the press seal. On each side area of the runners, a cut is formed in a shape of a V wedge 34 corresponding to the shape of the formed notches 24 located on the ribs 23. When the runners 28 are slid over the ribs, the V wedges 34 mate with the notches 24, locking the runners thereto. Extending below each side of the runners 28 is a pair of extensions in the shape of bent ears 36 that can be displaced during the base assembly.

After the runners are properly seated the fuse wires 26 are then attached to the lead-in wires 16 and 18 by a welding operation or other suitable technique and then :are directed to the inside of the runners. One wire is attached to either side as can be more clearly seen in FIGURE 3.

As mentioned above, the tabs 36 are displaced during assembly. In this case, a ceramic yoke 40 is first fitted over the center reduced area 32 of the seal 22. The interior surface of the upstanding legs 44 of the yoke are provided with spaced-apart grooves 4-6 that mate with the track portion 30 of the runners 28. The purpose of the yoke 40 is to bridge, and contain, the runners 28 located on either edge of the press seal 22. Therefore, the yoke 40 is attached. by sliding the legs 44 along the press seal. The spaced-apart grooves 46 slide over the tracks 30 of the runners, and the base portion 46 in its seated position covers the lead-in wires 16 and 18. Fuse connections 28 are covered by the yoke and located at the base of the press 22.

After the ceramic yoke 40 is in place, the cars 36 of the connectors are bent back over the base of the yoke locking it to the press seal 22. This operation completes the assembly of the base to the seal of the lamp.

FIGURE 2 shows a completed lamp base assembly with a portion of one of the runners 28 and part of the yoke 40 broken away, to show, in particular, the attachment of the fuse wires 26 to the inside of one of the runners and how the ears 36 are bent to retain the yoke in place.

Referring to FIGURE 3, a suitable ceramic socket 50 for the above described lamp is fitted with a pair of electrical spring leaves 52 that are secured to the base of the socket by suitable screws 54. An extension 56 from the screws extends out from the socket for provision of a suitable electrical source. The upstanding legs 58 of the leaves 52 extend into the interior of the socket through slots 60 in the base. The upper ends of the leaves 52 are made as V forms 62 and are spring biased inwardly.

With this configuration, at based lamp such as shown and described in this disclosure and shown in FIGURE 2 can be snap fitted into a socket described above. FIG- URE 3 illustrates a based lamp in engagement with its mating socket 50 and in position matching V forms 62 of the leaves, with the V wedges 24 of the runners 28.

It is apparent that changes and modifications may be made within the spirit and scope of the instant invention. It is our intent, however, to be limited only by the scope of the appended claims.

What we claim is:

1. In an incandescent lamp having a press seal, the combination comprising: indentation means formed in said press seal; a pair of metal runners positioned on each side of said press seal, said runners having retaining means formed in their inner sides and outwardly directed tracks on their outer sides; said retaining means adapted to mate with said indentation means, a ceramic yoke having grooves on the inner surfaces of its legs, said yoke being fitted upon said tracks of said runners, thereby making a unitary base structure.

2. The lamp according to claim 1 wherein said runners have ears depending from the lower surface thereof, said ears being bent over the bottom of said yoke and utilized to hold said yoke to said base.

3. An incandescent lamp comprising; a lamp envelope, a filament and lead-in wires extending from said filament through a press seal; said press seal having a pair of indentations positioned on their sides; a pair of metal runners having retaining means formed on their outer sides and outwardly directed tracks on their inner sides; said runners positioned on either edge of said press seal, whereby said retaining means of said runners mate with said indentation of said seal; said lead-in wires connected to said side runners; a ceramic yoke having grooves positioned on the inner side of its legs, whereby said grooves mate with said tracks of said runners, thereby holding said runners on said seal.

4. A tubular lamp having a press seal disposed at one end thereof, said lamp comprising: a pair of metal runners; retaining means including tracks disposed on said runners; a ceramic yoke means disposed over said seal in juxtaposition to said runners; said yoke having mating grooves to fit onto said tracks whereby said runners will be securely held upon said press seal.

References Cited UNITED STATES PATENTS 3,256,507 6/1966 Ackerman 339176 X 3,283,286 11/1966 Webb et al 339- X FOREIGN PATENTS 1,215,134 11/1959 France.

RICHARD E. MOORE, Primary Examiner.

U.S. Cl. X.R. 339176 

